Services

Single and Multi-Beam Sonar Surveys

Spicer Group uses single-beam and multi-beam sonar technology to collect high-density underwater topography of rivers, lakes, streams, and other bodies of water. This detailed 3D sonar data is useful for a variety of applications, including bridge scour analysis, hydraulic surveying and modeling, pre and post dredge volume calculation surveys, and other mapping solutions.

Single-beam and multibeam surveying consists of an echosounder mounted to a vessel that emits sound waves into the water and then receives the reflection or echo from the bottom surface. The time of travel of these sound waves, along with precise RTK/IMU positioning information, is recorded and interpreted to accurately represent the bottom topography of a body of water. Spicer Group owns and operates single-beam and multi-beam systems depending on the project specifications and level of detail desired.

Spicer Group’s hydrographic team has performed hundreds of shallow-water bathymetric surveys for local, state, and federal agencies, marina owners, lake associations, and contractors. Our hydrographic surveying team consists of professional surveyors with decades of traditional and hydrographic surveying experience.

Projects

Lafayette Bridge Mobile LiDAR and Multibeam Survey

Multibeam sonar technology was used to perform a hydraulic survey to support hydraulic analysis for the Lafayette Bascule Bridge over the East Channel of the Saginaw River in Bay City, MI. The purpose of the hydraulic survey was to obtain geometric data on the stream channel upstream and downstream of the bridge and determine the bottom topography and elevations immediately surrounding the bridge.

Utilizing multibeam sonar technology and our mobile LiDAR system, Spicer Group completed LiDAR and sonar acquisition using the same vessel. The dense 3D data provided high-resolution mapping data of the channel bottom, including the vertical surface of the bridge pier structures. The high-resolution data provides engineers a highly detailed image of the severity of scour around each bascule pier. In addition, since scanning covered shoreline to shoreline, our team extracted the required hydraulic cross sections from the data to support development of the HEC-RAS model.

The mobile LiDAR data collected from the marine vessel was combined with the LiDAR collected from a truck on top of the bridge, providing a rich 3D point cloud of the entire bridge structure from the waterline up. Detailed 3D mapping was then completed using the LiDAR data.

M-35 Multibeam Survey

A hydraulic survey was conducted using multibeam sonar technology on the M-35 bridge over the Cedar River in the Upper Peninsula of Michigan. A hydraulic analysis for scour due to past and future dredging required to maintain the nearby marina was requested by the Michigan Department of Transportation. This included the collection of geospatial data of the stream channel upstream and downstream of the structure.

Spicer Group employed its NORBIT Wideband Multibeam Sonar System to accomplish this task. With the compact system mounted on our 18’ survey vessel, our hydrographic survey team was able to navigate the shallow waters of the Cedar River and collect the required 3D river bottom data in an efficient and safe manner. Along with the main channel of the river, data was collected on multiple secondary channels and of and around the bridge piers. This high-density data will be valuable for the design of scour countermeasures around the piers in the future.

MDOT Statewide Scour Analysis & Underwater Inspections

Using multibeam sonar technology, Spicer Group’s hydrographic team collected high-density river bottom topography around the substructure units of major bascule bridges throughout Michigan. As part of the recurring Federal Highway Administration’s underwater bridge inspection requirements, multibeam technology was used in order to capture detailed 3D terrain data on the river bottoms near the bridge piers. The required dive inspections were also performed, however using multibeam sonar, our team was able to capture complete river bottom coverage.

Once processed to survey control, the data was reviewed and compared to the dive inspection results for consistency. In addition, developing scour holes can be accurately measured and analyzed over time. Subsequently, since the data is tied to survey control, it can then be used to develop detailed terrain surface models, cross sections can be extracted from the dataset, and scour countermeasure plans can be developed.

Tittabawassee River Multibeam Bathymetric Survey

Spicer Group was contracted to perform a multibeam bathymetric survey of a portion of the Tittabawassee River near Saginaw, Michigan. The existing bottom topography and elevations of the river channel was requested. In total, nearly 7 miles of river corridor was surveyed to produce high-resolution, spatially accurate 3D data.

The hydrographic survey team at Spicer Group had to endure shallow water conditions and high flow rates of the Tittabawassee River to capture the necessary data. With a NORBIT Wideband Multibeam Sonar System mounted on Spicer’s 18’ survey vessel, the team successfully acquired 3D topographic data on the river bottom quickly, efficiently, and most important, safely. 100% river bottom coverage was obtained for complete bank to bank coverage.